Slack adjuster for railway brakes



May 30, 1933. J J TATUM 1,912,321

SLACK ADJUSTER FOR RAILWAY BRAKES Filed Sept. 8, 1930 3 Sheets-Sheet l May 30, 1933. J. J. TATUM 1,912,321

SLACK ADJUSTER FOR RAILWAY BRAKES Filed Sept. 8, 1950' 5 Sheets-Sheet 2 IIIIIIFIIH May 30, 1933. J. J. TATUM 1,912,321

SLACK ADJUSTER FOR RAILWAY BRAKES Filed Sept. 8, 1950 Ii Sheets-Sheet 3 Jwumtoz Patented May 30, 1933 PATENT OFFICE JOHN J. TATUM, OF BALTIMORE, MARYLAND SLACK ADJUSTER FOR RAILWAY BRAxES Application filed September 8, 1930. Serial No. 480,548.

In my application for patent for slack adjuster for brakes for railway cars filed August 15, 1929, Serial No. 386,055, I have disclosed a slack adjuster for cars built of the conventional type, such as have the center sills of the car and the trucks and body structurally combined so that one will follow the other in movement over the rails under all conditions when being drawn in trains by the locomotive, regardless as to whether the train is being moved by momentum or by impact.

The present invention has for its object to provide a slack adjuster for railway cars coupled with what is known as a cushion underframe, in which the trucks are swivelled to the car body structure for relative steering movements to follow the line of the track, while the center sills and draft attachments are slidably 0 mounted on the body structure so as to adapt the body structure and center sills with the draft attachments to have relative longitudinal movements. In accordance with my invention, the parts of the slack adjuster are mounted upon the vcar body structure independently of and without connection with the center sills, and the truck levers of the foundation brake gear are pivotally mounted on the trucks for move- 9 ment therewith but are free from attachment to the center sills, so that, as the car body structure and center sills are free for relative longitudinal movements, the brakes may be applied and be adjusted without re- 5 striction or liability of damage under buffing and draft movements.

My present invention, therefore, resides broadly in a slack adjuster adapted for cars of the type described allowing free longi- 40 tudinal movement of the center sills independent of the movement of the car body, trucks and foundation brake gear and in which the truck dead lever is mounted independently of and without connection with the car body or center sills.

In the drawings:

Fig. l is a top plan view of a brake rigging embodying my invention on a car, the outlines of the car being shown in dotted lines.

Fig. 2 is a fragmentary longitudinal section of a portion of the under-frame of the car showing parts of the slack adjuster mounted thereon.

Fig. 3 is a plan View of in Fig. 2.

Fig. 4 is a side view looking toward the bearing bracket for the outer end of the slack adjuster shaft and showing the outer end of the shaft and the shaft locking means.

Fig. 5 is a transverse section through a part of the under-frame and showing one of the center sills and the parts of the slack adjuster. 7

Referring now more particularly to the drawings, 1 designates the car body, 2 a cushioned under-frame for the truck body,

3 the center sills, l the brake cylinder and piston, 5 the push rod extending into one end of the cylinder and connected to the piston therein, 6 the live cylinder lever coupled to the push rod, and 7 the rear cylinder lever coupled at one end by the rod 8 to the live cylinder lever, all of which parts of the car structure and foundation brake gear as thus far described may be constructed and ar ranged as in standard cars of the type referred to, wherein such parts of the brake gear are mounted on the cushioned underframe and trucks, and the center sills and 3 draft attachments have free longitudinal movement independent of the car body and its cushioned under-frame, trucks and foundation brake gear. My invention provides a slack adjuster which is mounted upon the car body under-frame structure and is movable with the car body and foundation brake gear attached to the car body and its underframe and operatively coupled to the rear cylinder lever mounted on the under-frame, and in turn coupled through the cylinder levers to live and dead levers on the trucks, which truck levers are entirely free from connection with the car body structure or center sills so that the range of brake cylinder piston travel can be regulated for simultaneous adjustment of slack of the brake gear on both body and trucks without the use of other adjusting means, and the brakes may be applied and be adjusted without restricthe parts shown 55 tion or liability of injury under buffing and draft strains.

In accordance with my invention, I provide a support and guide frame or casing 9, which is attached to the rear end of the brake cylinder and to a longitudinal underframe member 10, and which coacts with a bracket 11 fastened to a side sill 12 of the under-frame structure to support and guide the parts of the slack adjuster. The said frame or casing 9 comprises a pair of superposed members or sections 13 and 1 1 of a cross-sectional shape to form a casing extending longitudinally of the car and having longitudinal slots 15 at its sides. At their inner ends the members 13 and 14 have apertured portions or flanges 15 for at tachment by bolts or rivets 16 to bosses 17 formed on the rear end of the brake cylinder and at its outer end the member 13 is provided with an upstanding lug 17 fastened to the longitudinal under-frame member 10 to which the brake cylinder is attached, while the member 14 is formed at its outer end with an upstanding U-shaped or forked bracket 18 which is fastened to the said lug 17 of member 13, whereby the supporting guide frame or casing is rigidly mounted in position for movement with the undeuframe and brake gear carried thereby.

As shown, the frame or casing 9 receives the pivoted end of the lever 7 which extends thereinto through one of the slots 15, whereby such end of the lever is supported and guided. Arranged within and protected and guided by the frame or casing 9 is a flexible element 19, such as a chain or cable, which is fastened at one end to the entering end of lever 7 and at its opposite end to the inner end 20 of a winding shaft 20 journaled at said end in bearings in the fork arms 21 of the bracket 18 and journaled at its outer end in the bracket 11. The element 19 forms an adjustable fulcrum for the lever 7 which can be taken up or let out by the winding shaft to adjust the lever 6 and thereby adjust the brake rigging and regulate the travel of the brake cylinder piston to a desired degree, by which means the slack in the brake gear on both body and truck is simultaneously adjusted.

As shown, the outer end 20 of the shaft 20 is arranged beneath the side sill 12 within the clearance line of the car so as to comply with the American Railway Association regulations respecting clearance, ensuring avoidance of any restrictions against the operation of the car over any or all railroads in this country.

The shaft 20 is also located at one side of the center sills 3 in such manner that it and the levers 6 and 7 will lie clear of said sills, so that these parts may have free movement without interference with or by the center sills.

The said outer end 20 of the shaft 20 is rectangular and a ratchet wheel 20 is keyed thereto, there being, a pawl 22 suitably mounted on the bracket 11 to engage and hold the ratchet wheel in an adjusted position. To hold the pawl 22 in its interlocked relation to the ratchet wheel 2O under all service conditions, I provide a weighted dog 23 pivotally mounted at 24 and adapted for wedging engagement with the pawl, thereby holding the pawl against accidental disengagement from the ratchet wheel 20*. The dog is provided with a lug 25 which may be struck with a suitable instrument to move it from wedging relation with the pawl to permit of rotation of the ratchet wheel when desired. On revolving the shaft 20 for taking up slack in the brake gear the chain 19 is wound around the shaft, thereby pulling on the lever 7 to shift its fulcrum point and, through it, to adjust all brake connections on the under-frame and truck to take up slack therein and to simultaneously regulate the brake piston travel accordingly. This ensures'a proper and effective application of brakes, both hand and air, and avoids both excessive piston travel and excessive hand brake travel in the application of the brakes.

F ig. 5 shows one of the center sills 3 passing through and loosely surrounded by a transverse member 26 of the car under-frame structure 2, to which center sills there are no attachments of the car structure or brake gear, such sills being permitted to move longitudinally free and independent of the car structure and brake ear.

Having thus fully described my invention, I claim 1. In a slack adjuster for railway car brakes, a brake cylinder and piston, a push I rod extending into the cylinder at one end and connected to the piston therein, a live cylinder lever coupled to the push rod, a slotted support connected to the opposite end of the cylinder, a winding shaft carried by the support, a rear cylinder lever coupled to the live cylinder lever and having an end thereof extending into the support through the slot thereof, and a flexible element forming an adjustable fulcrum for the rear cylinder lever and arranged and guided in said support and connected to the shaft and to the guided end of said lever.

2. In a slack adjuster for railway car brakes, a brake cylinder and piston, a push rod extending into the cylinder at one end and connected to the piston therein, a live cylinder lever coupled to the push rod, a slotted support connected to the opposite end of the cylinder, a rear cylinder lever connected at one end to the live cylinder lever and having its opposite end extending into the support through the slot therein and guided thereby, a winding shaft journaled at one end in said support, and a flexible element in said support and connecting the shaft With the guided end of the rear cylinder lever, said shaft extending at its opposite end to a side of the ear and having means at said end for operating it.

In testimony whereof I afiix my signature.

JOHN J. TATUM. 

